"Not right." — said Ja Hyun, indifferently poking her notebook with his finger. Math was a difficult subject, but Ja Hyun was good at studying and was a nerd about studying. The guy did not look at her, but at the textbook and her notebook, periodically adjusting his glasses. He always had an indifferent, dispassionate character, which was sometimes replaced by a slight irritability. But he was patient with her.

"Here is the number pi. Read the task condition again."